DE102005030345B4 - High-frequency transmitting / receiving device - Google Patents

Abstract

High-frequency transmitting / receiving device with: • a high-frequency oscillator (11) for generating a high-frequency signal; • a branching device (12) connected to the high-frequency oscillator (11) and having two output areas (12b, 12c) for branching the high-frequency signal given by the high-frequency oscillator (11) and outputting the branched high-frequency signal components from one or the other of the two Output areas (12b, 12c) a modulator (13) connected to the one output area (12b) of the branching device (12) for modulating the branched high-frequency signal component and outputting a high-frequency signal intended for transmission; • a signal separation device (14) having a first connection (14a), a second connection (14b) and a third connection (14c) for receiving the high-frequency signal intended for transmission from the modulator (13) at the first connection (14a) for outputting the inputted to the first terminal (14a), high-frequency signal intended to be transmitted from the second terminal (14b) and outputting a high-frequency signal input from the second terminal (14b) from the third terminal (14c); • one ...

Description

BACKGROUND OF THE INVENTION

1. Field of the invention

The present invention relates to a mixer having a high-frequency transmitting / receiving device.

The invention also relates to a radar device having the high-frequency transmitting / receiving device and to a vehicle equipped with the radar device.

2. Description of the Related Art

So far, some examples of mixers of conventional design are known, such as those disclosed in Japanese Unexamined Patent Publications JP-A 10-242766 (1998) JP-A 2001-203537 . JP-A 2002-158540 and JP-A 2002-290113 have been disclosed. Among these is in the JP-A 10-242766 discloses a mixer using a nonradiative dielectric waveguide (hereinafter also referred to simply as "an NRD waveguide"). In the mixer, a Schottky diode serving as a high-frequency detection element and a substrate for supplying a bias voltage to the Schottky diode are disposed at the end of a dielectric strip line. Furthermore, a cavity resonator is arranged by means of a direction changer for changing the direction of a magnetic force line by 90 °. In the cavity resonator, a movable part for varying a resonant frequency is inserted. By moving the movable member, the resonant frequency of the cavity resonator is caused to vary, whereby a change in impedance can be achieved when the Schottky diode is viewed from the dielectric stripline.

Furthermore, high frequency transceivers designed to work with such a mixer and which are expected to find application in a millimeter wave radar module, a millimeter wave wireless radio communication apparatus, or the like have been proposed Find. Such a high-frequency transmitting / receiving apparatus is disclosed in, for example, Japanese Unexamined Patent Publication JP-A 2000-258525 disclosed. The in the JP-A 2000-258525 The disclosed radio frequency transceiver is of the type employing a pulse modulation scheme.

18 Fig. 10 is a schematic block circuit diagram showing the conventional high-frequency transmitting / receiving apparatus using the pulse modulation scheme. For example, the high-frequency transmitting / receiving apparatus consists of: a high-frequency oscillator 61 for generating a high-frequency signal; a relative to the output end of the high-frequency oscillator 61 connected branching device 62 for branching the high frequency signal so that the branched high frequency signal components at it have an output end 62b or their other issue end 62c can be issued; a relative to the one output end 62b the branching device 62 connected modulator 63 for modulating a part of the high frequency signal to output as a high frequency signal intended for transmission; a circulator 64 with a first connection 64a , a second connection 64b and a third port 64c of which the first connection 64a with the issue end 63a of the modulator 63 is connected, with one from the first port 64a input high-frequency signal to the second port 64b is output and one from the second port 64b output high-frequency signal to the third port 64c is issued; one with the second port 64b of the circulator 64 connected transmitting / receiving antenna 65 ; and one between the other output end 62c the branching device 62 and the third port 64c of the circulator 64 connected mixer 66 for mixing to the other output end 62c the branching device 62 as a local signal L0 output high-frequency signal with one through the transmitting / receiving antenna 65 received high frequency signal for generating an intermediate frequency signal.

It is known that in such a conventional high-frequency transmitting / receiving apparatus, a non-radiating dielectric line for use as a high-frequency transmission line is suitable for connecting among the high-frequency circuit elements and transmitting high-frequency signals.

Conventionally, a metal waveguide is generally used as a means for transmitting micro or millimeter waves. However, to meet the recent demand for a downsized high frequency module, developments are taking place to provide a high frequency module that uses a dielectric stripline as a waveguide for transmitting high frequency signals. Against this background, the non-radiative dielectric line as a new high frequency transmission line attracts much attention because of its ability to transmit high frequency signals with low loss.

17 is a partial perspective sectional view showing the basic structure of the non-radiative dielectric line. The non- Radiant dielectric line is constructed by a dielectric stripline 53 with a four-sided, for example rectangular, cross-sectional profile between two parallel plate conductors 51 and 52 is interposed, which are arranged in parallel at a predetermined distance a. In the present case, the relationship between the distance a and the wavelength λ of a high-frequency signal is preferably given by the expression: a ≦ λ / 2. By setting the distance a in this way, the high-frequency signals can be efficiently transmitted through the dielectric strip line 53 while the intrusion of external noise into the dielectric stripline 53 and the radiation of the high frequency signals are eliminated to the outside. It should be noted that the wavelength λ of a high-frequency signal represents a wavelength in the air (free space) at a usable frequency.

Further, examples of a conventional radar apparatus having the high frequency transmitting / receiving apparatus and a vehicle equipped with the radar apparatus are disclosed in, for example, Japanese Unexamined Patent Publication JP-A 2003-35768 disclosed.

However, conventional constructions have the following disadvantages. In such a mixer, as in the JP-A 10-242766 is disclosed, an adjusting mechanism (corresponding to the cavity resonator and the movable member, as exemplified) for adjusting mixing characteristics and the transfer characteristics of the mixer is formed so as to extend from the high-frequency detection element disposed at the end of the high-frequency transmission line. By adjusting its structural dimension, the electrical length of the adjustment mechanism by which radio frequency signals are transmitted is caused to vary, so that a change in impedance at the end of the adjustment mechanism can be achieved. In this case, however, there is a risk that the electrical length is varied in the structure in the presence of only a small clearance. This creates the problem of poor controllability. In an attempt to solve this problem, the removal of the game results in almost total impractical enlargement of the adjustment mechanism as a whole.

Further, the occurrence of oscillation and thermal expansion or contraction causes a deviation in the electrical length of the adjustment mechanism, such as the cavity resonator and the movable part. Thus, the electrical length can be easily deflected although it is optimally set in advance. This causes the problem of poor stability.

In addition, in the conventional high-frequency transmitting / receiving apparatus having such a mixer, because of a tuning inaccuracy or instability in the mixer, it is impossible to secure a uniform reception sensitivity. This causes the problem that it is difficult to stably obtain excellent properties.

On the other hand, in the in JP-A 2000-258525 disclosed radio frequency transmitting / receiving apparatus, which in the in 18 Shown in the schematic block diagram shown is a part of the mixer 66 reflected local signal L0 from the third terminal 64c to the first connection 64a of the circulator 64 , The resulting leakage RF signal is received by the modulator 63 which is held in an OFF state, completely reflected and then inconveniently from the transmitting / receiving antenna 65 As an unwanted high-frequency signal sent, which is why there is an undesirable reduction in the ON / OFF ratio, the intensity ratio between a signal intended for transmission high-frequency signal from the transmitting / receiving antenna 65 is sent when the modulator 63 is held in an ON state, and a radio frequency signal intended to be transmitted from the transmission / reception antenna 65 is sent when the modulator 63 is kept in an OFF state. This leads to a deterioration of the transmission / reception performance. That is, with the transmission of such an unwanted high-frequency signal, the high-frequency signal finds its way into a target high-frequency signal RF to be received. This causes a problem that a part of the high-frequency signal RF is likely not received correctly.

Furthermore, in the radar apparatus using such a high-frequency transmitting / receiving apparatus, a low-frequency high-frequency signal reflected from a far-off object to be detected is buried in a high-frequency signal transmitted when the modulator 63 is kept in an OFF state, namely noise. This results in a narrowing of the detectable amount and a susceptibility to erroneous detection, which causes a problem of delay in detection of an object to be detected.

Further, in the vehicle or small boat equipped with such a radar apparatus, an object to be detected is detected by the radar apparatus. In response to the detected information, the vehicle or small boat reacts appropriately, for example, avoids a collision and brakes. However, due to the delay of the target detection, after the detection process in FIG triggered an abrupt reaction to the vehicle or small boat.

From the EP 1 324 422 A2 a receiving / transmitting device is known. It has a transmission block, a reception block and an antenna block. The receive block has a coupler, a circulator and a mixer.

The US 4,492,960 describes a switchable mixer. The mixer has mixing diodes and biasing circuits therefor. The bias circuit is adjustable.

The U.S. 4,340,975 describes a microwave mixing circuit. This can have chip resistors.

The US 4870472 describes a resistance trimming method in which a diffused or implanted resistor in an IC is adjusted with current pulses. Also laser trimming is addressed.

The article "High-Speed ASK Transceiver ..." by Kuroki et al. In "IEEE Transactions on Microwave Theory and Techniques", Vol. 46 No 6, June 1998, shows in 7 an ASK transceiver with a Gunn oscillator, two circulators and a mixer.

The US 64147627 describes a radar device with a transmit-receive antenna.

SUMMARY OF THE INVENTION

The object of the invention is to provide a high-frequency transmitting / receiving device which prevents a part of a high-frequency signal intended for transmission from being transmitted as an unwanted signal when the modulator is kept in an OFF state.

This object is achieved with the features of claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the invention will be set forth in the following detailed description, wherein:

1 Fig. 12 is a schematic circuit diagram showing a mixer according to an embodiment;

2 is a schematic view of the mixer according to another embodiment, wherein 2A a top view of the mixer and 2 B shows a perspective view of the main part A of the mixer;

3 FIG. 11 is a plan view schematically showing an example of a high-frequency detection region of FIG 2 shown mixer;

4 a schematic view of an example of a trimmable chip resistor for forming an in 1 shown bias supply circuit, wherein 4A a top view of the trimmable chip resistor and 4B its side view shows;

5A to 5E are schematic plan views showing some other examples of the trim method for use with the in 4 show trimmable chip resistor shown;

6 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a first second embodiment;

7 is a plan view, the in 6 shows a radio frequency transceiver shown;

8th Fig. 12 is a perspective view schematically showing an example of a substrate having a diode for use in a nonradiative dielectric conduction type modulator;

9 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a second embodiment;

10 is a plan view, the in 9 shows a radio frequency transceiver shown;

11 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a third embodiment;

12 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a fourth embodiment;

13 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a fifth embodiment;

14 Fig. 10 is a schematic block circuit diagram showing a high frequency transmitting / receiving apparatus according to a sixth embodiment;

15 Fig. 12 is a graph showing the intensity Pa ₂ and Pb _{2 of} the high-frequency signals Wa ₂ and Wb ₂ observed in the application example of the high-frequency transmitting / receiving apparatus;

16 Fig. 12 is a graph showing the transmission power ON / OFF ratio characteristics as observed in the application example of the high-frequency transmission / reception apparatus;

17 is a partial perspective sectional view showing a basic structure of a non-radiative dielectric line; and

18 Fig. 10 is a schematic block circuit diagram showing an example of a conventional high frequency transmitting / receiving apparatus.

DETAILED DESCRIPTION

Now, features of the invention will be described below with reference to the drawings.

Initially, a mixer and a high-frequency radiating / receiving apparatus having the mixer will be described in detail with reference to the accompanying drawings.

1 Figure 4 is a schematic block diagram illustrating a mixer 6 according to one embodiment. 2 is a schematic view of the mixer 16 according to another embodiment, wherein 2A a top view of the mixer and 2 B a perspective view of the main part A shows that in 2A surrounded by a dotted line. 3 FIG. 10 is a plan view schematically showing an example of a high-frequency detection region of FIG 2 shown mixer 16 shows. 4 FIG. 12 is a schematic view of an example of a trimmable chip resistor for forming an in-chip. FIG 1 shown bias supply circuit C, wherein 4A a top view of the trimmable chip resistor and 4B its side view shows. The 5A to 5E FIG. 15 are schematic plan views illustrating some other examples of the trim method for use with the in FIG 4 show shown trimmable chip resistor. The 6 and 7 FIG. 12 is a schematic block diagram and a plan view, respectively, showing a high-frequency transmitting / receiving apparatus. FIG 110 according to a first embodiment show. 8th Fig. 12 is a perspective view schematically showing an example of a substrate having a diode for use in a nonradiative dielectric conduction type modulator. The 9 and 10 FIG. 12 is a schematic block diagram and a plan view, respectively, showing a high-frequency transmitting / receiving apparatus. FIG 120 according to a second embodiment show. 11 FIG. 12 is a schematic block diagram illustrating a radio frequency transceiver. FIG 130 according to a third embodiment. 12 FIG. 12 is a schematic block diagram illustrating a radio frequency transceiver. FIG 140 according to a fourth embodiment shows. 13 FIG. 12 is a schematic block diagram illustrating a radio frequency transceiver. FIG 150 according to a fifth embodiment shows. 14 FIG. 12 is a schematic block diagram illustrating a radio frequency transceiver. FIG 160 according to a sixth embodiment. 15 Fig. 12 is a diagram showing the intensity Pa ₂ and Pb _{2 of} the high-frequency signals Wa ₂ and Wb ₂ as observed in the application example of the high-frequency transmission / reception apparatus. 16 FIG. 15 is a diagram showing the transmission power ON / OFF ratio characteristics as observed in the application example of the high-frequency transmission / reception apparatus. 17 is a partial perspective sectional view showing the basic structure of a non-radiative dielectric line.

In the 1 . 4 and 5 denotes the reference numeral 1 a coupler; 2 denotes a Schottky diode provided as a high-frequency detection element; 3 denotes a trimmable chip resistor provided as a preset variable resistor; 4 denotes a throttle inductor; and 5 denotes a DC voltage source. Furthermore, the symbol indicates 3a a dielectric substrate; 3b denotes a resistance layer; 3c1 and 3c2 each designate an electrode; and 3d and 3d1 to 3d4 each designate a trim area.

Further referred to in the 2 . 3 and 6 to 14 the reference number 11 a high frequency oscillator; 12 denotes a branching device, for example a directional coupler; 13 denotes a modulator; 14 denotes a circulator provided as a signal separating device; 15 denotes a transmitting / receiving antenna; 16 denotes a mixer; 17 denotes a switch; 18 denotes an insulator; 19 denotes a transmitting antenna; 20 denotes a receiving antenna; 21 and 31 each denote a lower parallel plate conductor; 22 and 32 each denote a first dielectric strip line; 23 and 33 each denote a second dielectric strip line; 24 and 34 each denote a ferrite plate provided as a magnetic substance; 25 and 35 each denote a third dielectric strip line; 26 and 36 each denote a fourth dielectric strip line; and 27 and 37 each denote a fifth dielectric strip line. The reference numeral 28 and the symbols 38a and 38b each denote a non-reflective terminator. The reference number 39 denotes a sixth dielectric strip line; 40 and 44 each denotes a substrate; 41 and 46 each designate a reactor bias supply line; 42 and 47 each designate a connection terminal; 43 denotes a high-frequency modulation element; and 45 denotes a high-frequency detection element. The symbol 12a denotes an input end; 12b denotes an output end; 12c denotes the other output end; 13a and 18a each designate an input end; 13b and 18b each designate an output end; 14a . 24a and 34a each designate a first port; 14b . 24b and 34b each designate a second port; and 14c . 24c and 34c each designate a third connection. Furthermore, the reference numeral designates 71 a provided as a signal separating device RF selector switch; 72 denotes a second RF selector switch provided as a switching device; 73 . 74 denote a cavity branching hybrid coupler serving as a branching device; and 75 . 76 denote a second cavity branching hybrid coupler and a termination resistor, respectively, which serves as a signal isolation device. It should be noted that two parallel plate conductors in 2 not illustrated and that the upper parallel plate conductor both in 7 as well as in 10 not shown.

In the mixer 6 according to an embodiment as shown in the in 1 shown circuit diagram includes the coupler 1 two input ends 1a and 1b and one or two issue ends 1c (as exemplified). At the end of the issue 1c is the Schottky diode 2 arranged, which acts as a high-frequency detection element. With the Schottky diode 2 the bias supply circuit C is connected, which has the trimmable chip resistor 3 for controlling a bias current passing through the Schottky diode 2 passes. Furthermore, in the present construction, the coupler 1 from a high frequency transmission line, for example a coplanar line, for synthesizing two high frequency signals.

As described in more detail, the output end is 1C of the coupler 1 with an anode of the Schottky diode 2 connected and a cathode of the Schottky diode 2 is grounded. The bias supply circuit C is connected to an anode of the Schottky diode 2 connected.

On the other hand, in the mixer 16 according to another embodiment, as in 2 shown a directional coupler DC two input ends 26a and 27a as well as two issue ends 26b and 27b on. At each of the issue ends 26b and 27b is the Schottky diode 45 arranged, which acts as a high-frequency detection element (corresponding to the in 1 shown Schottky diode 2 ). With the Schottky diode 45 the bias supply circuit C is connected as those in 1 is shown. The bias supply circuit C includes the trimmable chip resistor 3 for controlling a bias current passing through the Schottky diode 45 passes. In the present construction, the directional coupler DC consists of a nonradiative dielectric line which is constructed by forming the dielectric stripline 26 and the dielectric stripline 27 sandwiched between two parallel plate conductors (not shown). The dielectric stripline 26 and the dielectric stripline 27 are next placed or coupled so that an electromagnetic coupling of a central region of the input end 27a and the issue ends 27b is achieved. With regard to each of the dielectric strip lines 26 and 27 For example, the non-radiative dielectric line has basically the same structure as that shown in FIG 17 shown in perspective partial sectional view. As in the 3 shown top view is the Schottky diode 45 continue with the in the choke bias supply line 46 trained connection port 47 connected. More specifically, the reactor bias supply line is made 46 from wide stripes 46a and narrow stripes 46b which are narrower in width than the wide strip formed of a conductive layer formed on a surface of the substrate 44 is trained.

The wide stripes 46a and the narrow stripes 46b are alternately and periodically spaced at a pitch of λ / 4 (where λ is the wavelength of one through the dielectric strip lines 26 and 27 is to be sent high-frequency signal). The connection port 47 is at a predetermined middle position of the throttle bias supply line 46 interposed. For easier understanding are in 3 the wide stripes 46a , the narrow stripes 46b and the connection port 47 shown in a mesh pattern. The wide stripes 46a , the narrow stripes 46b and the connection port 47 are formed so as to have the same centers in the width direction. The width direction is one to the extending direction of the line 46 and the thickness direction of the line 46 vertical direction. Seen from one side in the thickness direction, the wide strips have 46a , the narrow stripes 46b and the connection port 47 rectangular profiles on. A connection port 47a is with the wide stripes 46a and the narrow strip 46b located on an opposite side of the Schottky diode 45 a connection connection 47a in a one-piece body educated. The other connection port 47b is with the wide stripes 46a and the narrow strip 46b on the opposite side of the Schottky diode 45 a connection connection 47a are connected, formed in a one-piece body. That with the Schottky diode 45 connected substrate 44 is arranged so that in each case at the output ends 26b and 27b the dielectric strip lines 26 and 27 output high-frequency signals into the Schottky diode 45 enter.

Furthermore, in the constructions described so far, as in 1 shown circuit diagram, the bias supply circuit C with the throttle inductor 4 and the DC voltage source 5 Mistake. The throttle inductor 4 , the trimmable chip resistor 3 and the DC voltage source 5 are consecutive with the Schottky diode 2 connected. In other words, the choke inductor 4 is with the anode of the Schottky diode 2 connected and the trimmable chip resistor 3 is between the throttle inductor 4 and the DC voltage source 5 connected. It should be noted that the choke bias supply line 46 the throttle inductor 4 equivalent. The DC voltage source consists of a constant voltage source which outputs a predetermined DC voltage.

As in 4 is shown, there is the trimmable chip resistor 3 for example, from the dielectric substrate 3a made of a dielectric substance, for example alumina ceramic. On the dielectric substrate 3a , ie, a surface 3A of the dielectric substrate 3a in the thickness direction, is the resistance layer 3b made of a resistance material, for example, a Ni-Cr (nickel-chromium) alloy. At both end regions of the resistance layer 3b are the electrodes 3c1 and 3c2 connected so that they both end portions of the dielectric substrate 3a cover. The resistance layer 3b the trimmable chip resistor 3 is laser light emitted from a YAG (yttrium, aluminum, garnet) laser or the like device to oxidize a part of the resistive layer 3b irradiated to a suitable area, whereby the formed of an insulating metal oxide trim area 3d is formed. In this way it causes the resistance between the electrodes 3c1 and 3c2 varied. The two end regions of the resistance layer 3b in other words, are both end portions in a given direction along the one surface 3A of the dielectric substrate 3a in the resistance layer 3b , In the present case, both end regions are located in a longitudinal direction X1. The two end regions of the resistance layer 3a In other words, both end portions are in a given direction along the one surface 3A of the dielectric substrate 3a in the resistance layer 3a , In the present case, both end regions are located in a longitudinal direction X1. The electrodes 3c1 . 3c2 consist of metal materials with a lower resistance than the resistance layer 3b and are made by plating with solder, aluminum, copper or the like. The resistance layer 3b is realized by a thin metal film of parallelepipedic shape. The resistance layer 3b is formed in a region except for a peripheral region on a surface 3A of the dielectric substrate 3a in a thickness direction. The two end regions of the resistance layer 3b in a longitudinal direction are each in contact with the electrodes 3c1 . 3c2 ,

The trimmable chip resistor 3 covers the resistance layer 3b between the electrodes 3c1 and 3c2 , and may include a protective film that electrically insulates. The protective film transmits about 99% of the light from the YAG laser. By providing such a protective film, it is not necessary to perform a process of protecting the resistive layer 3b to perform after trimming. This facilitates a post-treatment. Furthermore, the resistance layer 3b protected by the protective film. As a result, the resistance is prevented from varying so that in the trimmable chip resistor 3 a stable resistance is maintained.

According to the mixers 6 . 16 Just like the mixer of conventional design, high-frequency signals come from the two input ends 1a and 1b ( 26a and 27a ) are mixed with each other (mixing) to produce an intermediate frequency signal. In general, mixing characteristics as well as the transfer characteristics of the mixer depend on a bias current passing through the Schottky diode 2 ( 45 ) goes through. In view of this, the trimmable chip resistor 3 between the DC power source 5 and the Schottky diode 2 ( 45 ) is arranged as a preset variable resistor for controlling the bias current. By properly adjusting the resistance of the trimmable chip resistor 3 by trimming or a similar technique, the bias current can be controlled so that the mixing characteristics and the transmission characteristics of the mixer are optimally tuned (tuning).

It should be noted that the mixing characteristics mainly relate to conversion gain characteristics defined by the relative intensity ratio between a mixed high frequency signal and an intermediate frequency signal to be output. On the other hand, the transfer characteristics of the mixer relate to the transfer characteristics of High frequency signals passing through the two input ends of the mixer.

Instead of the trimmable chip resistor 3 As shown herein, another type of preset variable resistor may be used, such as a mechanical trim resistor or a potentiometer, such as a rotary type or contact type potentiometer. In both cases, essentially the same effect can be achieved. However, the use of the trimmable chip resistor 3 Therefore, because despite the occurrence of an external vibration no resistance deviation takes place and because it offers high reliability in temperature and humidity fluctuations.

In particular, the trimmable chip resistor 3 designed as follows. As in 4 For example, YAG laser light becomes parallel to a width direction X2 of the resistance layer 2 B on an outer edge of the resistance layer 3b coming from the electrode 3c1 . 3c2 is free, applied from the outside, to form a linear oxidized area, which serves as a trim area 3d acts. The resistance of the trimmable chip resistor 3 changes with the area of the trim area 3d formed in the form of a linear oxidized region or the like shape. If the area of the trim area 3d is widened, the area of the cross section of the resistive layer decreases 3b through which a current flows, whereby the resistance is increased. If the resistance layer 3b is oxidized, for example, in a region where the laser light is applied, all parts from one surface to the other surface of the resistance layer 3b in a thickness direction, and in a region in which the laser light is applied becomes only a surface area of the resistance layer 3b oxidized in the thickness direction.

When the resistance of the trimmable chip resistor 3 is set, the initial value of the resistor is generally set in advance so that it is relatively small within a desired adjustment spectrum, so that the resistance can be adjusted so that it gradually increases. Before continuing the area of the trim area 3b by extending with a linear cutting, the width of the trim area is increased 3d is set to a predetermined value corresponding to the spot size of the YAG laser light. Then, when the YAG laser light is scanned in an axial direction, the area of the trimming area becomes 3d extended accordingly in the scanning direction. By repeatedly applying the YAG laser light to the same part in a pulsed process before subsequent scanning, drag control (trimming) can be performed with great accuracy.

In the embodiment, a part of the resistance layer becomes 3b is oxidized, reducing the resistance of the resistive layer 3b is varied. However, in another embodiment, a portion of the resistive layer 3b be cut away by a laser, reducing the resistance of the resistive layer 3b is varied.

The trim area 3d is not on the in 4 limited shown linear oxidized area. For example, as in the in 5A shown in plan view, the trim area 3d can be obtained by a similar linear oxidized region in the central portion of the resistive layer 3b how an island is formed. Similarly, in the 5B a similar linear oxidized region as the first oxidized region 3d1 formed and also another linear oxidized region is used as the second oxidized region 3d2 in one of the first oxidized region 3d1 easily removed position formed (double-oxidized configuration). The second oxidized area 3d2 becomes shorter than the first oxidized area 3d1 executed.

An extension direction of the first oxidized region 3d1 and an extension direction of the second oxidized region 3d2 are parallel to each other. The first oxidized area 3d1 and the second oxidized region 3d2 are designed so that they are not connected. It is desirable that one end of the first oxidized region 3d1 on the side of the second oxidized region 3d2 and an end of the second oxidized region 3d2 on the side of the first oxidized area 3d1 are formed at a predetermined distance apart in a direction opposite to the extending direction of the first oxidized region 3d1 and the second oxidized region 3d2 and a thickness direction of the resistance layer 2 B , ie the longitudinal direction X1 of the resistance layer 2 B , is vertical.

In the in 5C example shown is, in contrast to in 5B shown double-oxidized configuration, the second oxidized region 3d2 on the first oxidized area 3d1 opposite side of the resistance layer 3b educated. In the in 5D shown in addition to two linear oxidized areas 3d1 and 3d2 , in the 5C as the double-oxidized configuration are shown, another two linear oxidized regions 3d3 and 3d4 be formed in a comb-tooth shape (serpentine-oxidized configuration). By forming such trim areas 3d and 3d1 to 3d4 as they are in the 5B to 5D As shown, trimming-based adjustment can be achieved with greater accuracy. This is because the resistor with greater precision in the presence of the second oxidized areas 3d2 and 3d4 can be determined. By the trim area 3d is formed in such a way, the line length of the resistance layer 3b can be increased and therefore the resistance can be increased.

Furthermore, as in 5E shown is the trim area 3d also be prepared as an L-shaped oxidized region consisting of a first linear oxidized region 3d5 which is formed parallel to the width direction X2 and a second linear oxidized region 3d6 which is formed by making a direction for scanning the laser light traveling at an almost right angle with respect to the first linear oxidized region 3d5 is bent and which is in the longitudinal direction of the resistance layer 3b extends. A length of the first linear oxidized region 3d5 parallel to the width direction X2 of the resistance layer 3b is chosen to be equal to or less than half the length of the resistive layer 3b in the width direction is X2. Further, a length of the third linear oxidized region becomes 3d6 in an extension direction, in other words, a length of the second linear oxidized region 3d6 parallel to the longitudinal direction X1 of the resistance layer 3b selected to be longer than a length of the first linear oxidized region 3d5 parallel to the width direction X2 of the resistance layer 3b is.

In this case, one on the resistance layer 3b acting load can be made easier, which is why the resistance layer 3b less prone to a microcrack. This helps to reduce a resistance deviation that occurs under the influence of microcracking.

It should be noted that although trimming by means of a single trimmable chip resistor 3 can be achieved in a sufficiently wide adjustment range, it is also possible, several together in series or parallel connected trimmable chip resistors 3 to use.

The trimmable chip resistor 3 is disposed so as to be exposed outside when the mixer is attached to the high-frequency transmitting / receiving apparatus. This allows the resistance of the trimmable chip resistor 3 to vary in a state in which the mixer is attached to the high-frequency transmitting / receiving device.

According to the embodiments of the mixer 6 . 16 is due to the provided as a preset variable resistor trimmable chip resistor 3 in accordance with the Schottky diode ( 2 . 45 ) serving as a high-frequency detection element, such as the property of noise generated by the resistance component of the high-frequency detection element and the manner of mounting the Schottky diode (FIG. 2 . 45 ), a bias current at the time of adjusting properties, for example, the mixing properties and the transfer characteristics of the mixer, is set at an appropriate value, and at all other times, such as the occasion when the mixer has been incorporated into a product Pre-flow maintained at the preset value. In contrast to the case where the electrical length of the adjustment mechanism, which is designed to extend from the high-frequency detection element arranged in the high-frequency transmission line, is controlled, not only is it possible to have a mechanical structure present in the structure It can also stabilize the working condition after setting. As a result, the properties including mixing property and transfer characteristics of the mixer can be tuned with high accuracy and stability. Furthermore, in the absence of a moving part, the trimmable chip resistor 3 cause a certain resistance to be stably maintained despite the occurrence of an external force such as vibration after adjustment. Thus, the trimmable chip resistor 3 suitable for use as a preset variable resistor from the standpoint of stable tuning.

It should be noted that instead of the trimmable chip resistor 3 as shown here, another type of preset variable resistor as described above can be used as long as it exhibits the following characteristics: its resistance can be adjusted to vary arbitrarily; it prevents a preset value from being unintentionally varied and the resistance is adjustable at least dozens of times. As the preset variable resistor, an irreversible resistor is preferable, for example, the trimmable chip resistor 3 , used.

In the mixer 6 . 16 For example, the high-frequency transmission line is not limited to a coplanar line or a non-radiating dielectric line, but may have another configuration, for example, a strip line, a microstrip line, a coplanar line with a ground, a slot line, a waveguide, or a dielectric waveguide ,

Next, the high-frequency transmitting / receiving apparatus 110 described according to the first embodiment. As in the in 6 shown in the block diagram, the high-frequency transmitting / receiving device consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected branching device 12 for branching the high frequency signal so that the branched high frequency signal components at it have an output end 12b or their other issue end 12c can be issued; one with the one output end 12b the branching device 12 connected modulator 13 for modulating the at the one output end 12b a branched high-frequency signal component to output a high-frequency signal intended for transmission; a circulator made of a magnetic substance 14 with a first connection 14a , a second connection 14b and a third port 14c which are arranged around the circumference of the magnetic substance, of which the first terminal 14a an output from the modulator 13 receives, wherein a high-frequency signal inputted from one of the terminals is in turn output from the other adjacent terminal, in order from the first to the third terminal; one with the second port 14b of the circulator 14 connected transmitting / receiving antenna 15 ; and a mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 includes two input ends 16a and 16b , each between the other issue end 12c the branching device 12 and the third port 14c the circulator are connected to those at the other output end 12c branched high frequency signal component with one through the transmitting / receiving antenna 15 to mix received radio frequency signal to produce an intermediate frequency signal.

In other words, the branching device 12 has two output areas 112b . 112c on. An input area 112a the branching device 12 is with the high-frequency oscillator 11 connected. The branching device 12 branches that through the high-frequency oscillator 11 given high-frequency signal, so that the branched high-frequency signal components from their one output range 112b or their other output range 112c can be issued. The modulator 13 is with the one output area 112c and modulates the branched high-frequency signal component to output a high-frequency signal intended for transmission to the one output section. If the intended for transmission high frequency signal from the modulator 13 to the first connection 14a is given, acting as the signal separating device circulator 14 the intended for transmitting high-frequency signal from the first port 14a is entered from the second port 14b off and outputs a high frequency signal coming from the second port 14 is entered from the third port. In the mixer 16 is an input end 16a with the other output area 112c the branching device 12 connected and the other input end 12b is with the third connection 14c connected. The mixer 16 mixes those from the other output area 112c output high-frequency signal component with that by the transmitting / receiving antenna 15 received high frequency signal to output an intermediate frequency signal.

In the high-frequency transmitting / receiving apparatus, a transmission coefficient is preferably between the two input ends 16a and 16b of the mixer 16 so determined that the following expression holds: Pa ₂ = Pb ₂ . In particular, a modulator placed in the OFF state is 13 high frequency signal defined as Wa ₂ , and a high-frequency signal from the other output range 112c the branching device 12 by means of the mixer 16 and the circulator 14 to the issue end 13b the output range of the modulator 13 sent and then from the issue end 13b of the modulator 13 is defined as Wb ₂ . The intensity of the high-frequency signal Wa ₂ is represented by Pa ₂ , while the intensity of the high-frequency signal Wb _{2 is represented} by Pb ₂ . Under these conditions, the transmission coefficient is set so that the expression Pa ₂ = Pb ₂ holds.

Also, in the high frequency transmitting / receiving apparatus, the distance (line length) between the one output end is preferable 12b the branching device 12 and the modulator 13 or the distance (line length) between the output end 12c the other output area 112c the branching device 12 and the issue end 13b of the modulator 13 , where the mixer 16 and the circulator are interposed, determined in such a manner that the following expression holds: δ = (2N + 1) · π (N is an integer), where δ indicates the phase difference between the high-frequency signals Wa ₂ and Wb ₂ a center frequency is. Thus, the phase difference δ given by the expression δ = (2N + 1) · π becomes the line length of the first dielectric strip line 22 that the high-frequency oscillator 11 and the modulator 13 connects and part of the branching device 12 represents, as in 7 is shown extended while the line length of the second dielectric stripline 23 that the modulator 13 and the circulator 14 connects, is shortened accordingly or the line length of the second dielectric strip line 23 is extended while the line length of the first dielectric stripline 22 is shortened accordingly. In this case, it is not necessary to arrange other circuit elements than. modulating the modulator, making adjustment easier. It should be noted that it is necessary at this time, the Position of the mutually adjacent or coupled regions of the first dielectric strip line 22 and the fifth dielectric stripline 27 (the branching device generation section 12 ) maintain.

Furthermore, the high frequency transceiver uses 110 , in the 6 is shown a non-radiative dielectric line as a high-frequency transmission line to provide a connection among the constituent elements. The non-radiative dielectric line used basically has the same structure as that used in the present invention 17 shown in perspective partial sectional view.

As in the 7 shown top view, there is the high-frequency transmitting / receiving device 110 , in the 6 is shown, more precisely from two parallel plate conductors 21 which are arranged at a pitch equal to or less than half the wavelength of a high frequency signal (one of the parallel plate conductors is not shown). Between the two parallel plate conductors 21 are arranged: a first dielectric strip line 22 ; the one end of the first dielectric stripline 22 connected high-frequency oscillator 11 for frequency modulating a high frequency signal output from a high frequency diode and outputting the frequency modulated high frequency signal passing through the first dielectric strip line 22 has propagated; the modulator 13 an input end 13a and an issue end 13b having the other end of the first dielectric stripline 22 connected to the high frequency signal in the direction of the input end 13a to reflect or towards the output end 13b to pass in response to a pulse signal; a second dielectric stripline 23 whose one end is at the output end 13b of the modulator 13 connected is; the circulator 14 made of a ferrite plate 24 is formed, which is parallel to the parallel plate conductors 21 is arranged, which has a first connection 24a , a second connection 24b and a third connection 24c which is around the circumference of the ferrite plate 24 are arranged around and each act as high-frequency signal input and output ends, of which the first terminal 24a to the other end of the second dielectric stripline 23 is connected, wherein a high-frequency signal inputted from one of the terminals is in turn output from the other adjacent terminal, in the order from the first to the third terminal; a third dielectric stripline 25 and a fourth dielectric stripline 26 Radial around the circumference of the circulator 14 performing ferrite plate 24 are arranged, whose one ends with the second connection 24b or the third connection 24c are connected; that with the other end of the third dielectric stripline 25 connected transmitting / receiving antenna 15 ; a fifth dielectric stripline 27 whose center region is in close proximity to the middle region of the first dielectric stripline 22 is placed or coupled to it, in other words, its central region in an extension direction in the immediate vicinity of a central region of the first dielectric stripline 22 is placed in a direction of extension and branched to branch and send a part of a high frequency signal passing through the first dielectric stripline 22 propagates; one with a side end of the high-frequency oscillator 11 the fifth dielectric stripline 27 connected non-reflective terminator 28 ; and the mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 is between the other end of the fourth dielectric strip line 26 and the other end of the fifth dielectric strip line 27 connected to a high frequency signal coming from the fifth dielectric stripline 27 is entered, with one from the circulator 14 entered high-frequency signal, after passing through the transmit / receive antenna 15 has been received to mix to generate an intermediate frequency signal.

In the present construction, a transmission coefficient is preferably between the two input ends 16a and 16b of the mixer 16 so determined that the following expression holds: Pa ₂ = Pb ₂ . In particular, a high-frequency signal that is in the second dielectric strip line 23 after having been input by the modulator placed in an OFF state 13 gone through, ie the modulator 13 in a state in which no bias is applied, defined as Wa ₂ , and a high-frequency signal formed from the mutually adjacent or coupled regions of the first dielectric strip line 22 and the fifth dielectric stripline 27 and the mutually adjacent or coupled regions of the fifth dielectric strip line 27 and the fourth dielectric stripline 26 to the issue end 13b of the modulator 13 through the circulator 14 sent, then from the issue end 13b of the modulator 13 and finally into the second dielectric stripline 23 has been entered is defined as Wb ₂ . The intensity of the high-frequency signal Wa ₂ is represented by Pa ₂ , while the intensity of the high-frequency signal Wb _{2 is represented} by Pb ₂ . Under these conditions, the transmission coefficient is set so that the expression Pa ₂ = Pb ₂ holds. The transmission coefficient between the two input ends 16a and 16b of the mixer 16 can be adjusted to a desired value by applying the mixer's tuning function.

Also, in the present construction, the distance (line length) between the mutually adjacent or coupled portions of the first dielectric strip line is preferable 22 and the fifth dielectric stripline 27 (the section for creating the branching device 12 ) and the other end of the first dielectric stripline 22 (corresponding to the distance (line length) between the branching device 12 and the modulator 13 ) or the sum of the distance (line length) between the mutually adjacent or coupled regions of the first dielectric strip line 22 and the fifth dielectric stripline 27 and the other end of the fifth dielectric strip line; the line length of the fourth dielectric strip line 26 ; and the line length of the second dielectric strip line 23 (corresponding to the distance (line length) between the side area of the mixer 16 the branching device 12 and the modulator 13 ) is determined in such a way that the following expression holds: δ = (2N + 1) · π. In particular, a modulator placed in the OFF state is 13 defined high-frequency signal as Wa ₂ and a high-frequency signal, which consists of the mutually adjacent or coupled regions of the first dielectric strip line 22 and the fifth dielectric stripline 27 to the issue end 13b of the modulator 13 through the mixer 16 , the fourth dielectric stripline 26 and the circulator 14 sent and then from the issue end 13b of the modulator 13 is defined as Wb ₂ . δ stands for the phase difference between the high frequency signals Wa ₂ and Wb ₂ at a center frequency. Under these conditions, the line length is set so that the expression δ = (2N + 1) · π holds. It should be noted that, as described above, the first and fifth dielectric strip lines 22 and 27 the branching device 12 represent at their mutually adjacent or coupled areas.

In 7 correspond to the first connection 24a , the second connection 24b and the third connection 24c each to the first port 14a , the second port 14b and the third port 14c , in the 6 are shown.

In the present construction, the modulator is 13 designed as follows. As in the 8th shown in perspective view is the connection terminal 42 at a middle position of the reactor bias supply line 41 arranged on a surface of the substrate 40 is formed in a thickness direction, and the diode acting as a high-frequency modulation element 43 is with the connection port 42 connected, whereby a high frequency modulator is made. The high frequency modulator is between the first dielectric stripline 22 and the second dielectric stripline 23 inserted so that one out of the first dielectric stripline 22 output high-frequency signal in the diode 43 entry. The choke bias supply line 41 has a similar shape to the above-described reactor bias supply line 46 , in the 3 is shown. In 8th For convenience of understanding, the choke bias supply line is for convenience 41 shown with diagonal lines. The serving as a high-frequency modulation element diode 43 can be realized by using a PIN diode. Instead of the diode 43 For example, a transistor or a monolithic microwave integrated circuit (MMIC) may also be used.

Such a transmissive modulator as just described above is for use as the modulator 13 the radio frequency transceiver suitable. Instead of the transmissive modulator, a switching device may be used which allows the transmission and reflection of radio frequency signals, for example a semiconductor switch or a MEMS (microelectromechanical system) switch.

The in the 6 and 7 shown radio frequency transceiver 110 is similar to the conventional high frequency transceiver in terms of operation. However, in the high-frequency transmitting / receiving apparatus 110 due to the mixer 16 the mixing characteristics and the transfer characteristics of the mixer according to the characteristic of the high-frequency detecting element serving Schottky diode 45 and the manner of mounting the Schottky diode 45 be suitably matched. Thereby, a high-power high-frequency transmission / reception apparatus can be realized which exhibits excellent receiving sensitivity with stability.

Another advantage is the transmission coefficient between the two input ends 16a and 16b of the mixer 16 so determined that the expression Pa ₂ = Pb ₂ holds. In particular, a high frequency signal generated by the modulator placed in an OFF state 13 is defined as Wa ₂ , and a high frequency signal coming from the other output range 12c the branching device 12 by means of the mixer 16 and the circulator 14 to the issue end 13b of the modulator 13 sent and then from the issue end 13b of the modulator 13 is defined as Wb ₂ . The intensity of the high-frequency signal Wa ₂ is represented by Pa ₂ , while the intensity of the high-frequency signal Wb _{2 is represented} by Pb ₂ . Under these conditions, the transmission coefficient is set so that the expression Pa ₂ = Pb ₂ holds. In this case The high-frequency signals Wa ₂ and Wb ₂ interfere with each other to cause attenuation. This makes it possible to realize a high-frequency transmission / reception apparatus which is remarkable for its simple construction but nevertheless offers excellent transmission and reception performance with a high transmission power ON / OFF ratio by preventing a part of the antenna from being used Send intended radio frequency signal is sent as an unwanted signal when the modulator 13 is kept in an OFF state.

By setting the intensity Pa _{2 of} the high-frequency signal Wa ₂ (unit: watts) substantially equal to the intensity Pb _{2 of} the high-frequency signal Wb ₂ (unit: watts), the high-frequency signals Wa ₂ and Wb _{2 can} be made to effectively interfere with each other weaken each other. That is, when the high-frequency signals Wa ₂ and Wb _{2 are} synthesized, the resulting signal intensity is much smaller than the actual sum of the intensity of Pa ₂ and Pb ₂ : Pa ₂ + Pb ₂ . For this reason, it is desirable to satisfy the expression Pa ₂ = Pb ₂ . Theoretically, such a phenomenon occurs when two high-frequency signals interfere with each other. In contrast, when the relationship between Pa ₂ and Pb _{2 is given} by: Pa ₂ ≠ Pb ₂ , the high-frequency signals Wa ₂ and Wb ₂ do not sufficiently interfere with each other, with the result that there is no large difference between the signal intensity observed when the radio frequency signals Wa ₂ and Wb _{2 are} synthesized, and gives the actual sum of the intensity Pa ₂ and Pb ₂ : Pa ₂ + Pb ₂ . This makes it impossible to suppress generation of an unwanted high-frequency signal when the modulator 13 is kept in an OFF state, resulting in the failure to achieve a high ON / OFF ratio.

As yet another advantage is the distance (line length) between the one output end 12b the branching device 12 and the modulator 13 or the distance (line length) between the other output end 12c the branching device 12 and the issue end 13b of the modulator 13 , where the mixer 16 and the circulator 14 δ = (2N + 1) · π (N is an integer), where δ is a center frequency for the phase difference between the high frequency signals Wa ₂ and Wb ₂ . In this case, in the region between the issue end 13b of the modulator 13 and the circulator 14 the high-frequency signals Wa ₂ and Wb ₂ are synthesized in phase opposition and cancel each other, thereby extremely efficiently damping. Thereby, a high frequency transmitting / receiving apparatus can be realized which offers excellent transmission and reception performance with a high transmission power ON / OFF ratio by effectively preventing a part of a radio frequency signal intended for transmission from being sent as an unwanted signal, if the modulator 13 is kept in an OFF state.

Further, in the above embodiment, an output end of the mixer 16 preferably with a switch 17 which performs opening / closing (switching) in accordance with an external opening / closing control signal. When the switch 17 for performing the opening / closing (switching) in accordance with the control signal for opening / closing from the outside at the output end of the mixer 16 is provided, ie the output area 16c for outputting the generated intermediate frequency signal, even if, for example, insufficient insulation between the first terminal 14a of the circulator 14 and the third port 14c causes a portion of the radio frequency signal intended to be transmitted to the third port 14c of the circulator 14 licks, then the switch can 17 be operated so that such intermediate frequency signal is turned off so as not to output the intermediate frequency signal to the leaked high frequency signal, and therefore the high frequency signal to be received can be generated so that it is easy to identify.

Next, the high-frequency transmitting / receiving apparatus 120 described according to the second embodiment. As in the in 9 As shown in the block diagram shown, the high-frequency transmitting / receiving device consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected branching device 12 for branching the high frequency signal so that the branched high frequency signal components at it have an output end 12b or their other issue end 12c can be issued; one with the one output end 12b the branching device 12 connected modulator 13 for modulating the at the one output end 12b a branched high-frequency signal component to output a high-frequency signal intended for transmission; an insulator 18 whose one end 18a with an issue end 13b of the modulator 13 connected to pass the intended high-frequency signal for transmission from its one end 18a to its other end 18b ; one with the insulator 18 connected transmitting antenna 19 ; one relative to the other output end 12c the branching device 12 connected receiving antenna 20 ; and a mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 includes two input ends 16a and 16b , each between the other issue end 12c the branching device 12 and the receiving antenna 20 connected to the other end of the output 12c branched High frequency signal component with a through the receiving antenna 20 to mix received radio frequency signal to produce an intermediate frequency signal.

Furthermore, the in 9 A radio frequency transceiver shown has a non-radiative dielectric line as a high frequency transmission line for establishing connection among constituent elements. The non-radiative dielectric line used basically has the same structure as that used in the present invention 17 shown in perspective partial sectional view.

As in the 10 shown top view, there is the high-frequency transmitting / receiving device 120 , in the 9 is shown, more precisely from two parallel plate conductors 31 which are arranged at a pitch equal to or less than half the wavelength of a high frequency signal (one of the parallel plate conductors is not shown). Between the two parallel plate conductors 31 are arranged: a first dielectric strip line 32 ; the one end of the first dielectric stripline 32 connected high-frequency oscillator 11 for frequency modulating a high frequency signal output from a high frequency diode and outputting the frequency modulated high frequency signal passing through the first dielectric strip line 32 has propagated; the modulator 13 an input end 13a and an issue end 13b having the other end of the first dielectric stripline 32 connected to the high frequency signal in the direction of the input end 13a to reflect or towards the output end 13b to pass in response to a pulse signal; a second dielectric stripline 33 whose one end is at the output end 13b of the modulator 13 connected is; the circulator 14 made of a ferrite plate 34 is formed, which is parallel to the parallel plate conductors 31 is arranged, which has a first connection 34a , a second connection 34b and a third connection 34c which is around the circumference of the ferrite plate 34 are arranged around and each act as high-frequency signal input and output ends, of which the first terminal 34a to the other end of the second dielectric stripline 33 is connected, wherein a high-frequency signal inputted from one of the terminals is in turn output from the other adjacent terminal, in the order from the first to the third terminal; a third dielectric stripline 35 and a fourth dielectric stripline 36 Radial around the circumference of the circulator 14 performing ferrite plate 34 are arranged, whose one ends with the second connection 34b or the third connection 34c are connected; that with the other end of the third dielectric stripline 35 connected transmitting antenna 19 ; a fifth dielectric stripline 37 whose center region is in close proximity to the middle region of the first dielectric stripline 32 is placed or coupled to it, for branching and transmitting a part of a high frequency signal passing through the first dielectric stripline 32 propagates; one to the other end of the fourth dielectric stripline 36 connected non-reflective terminator 38a ; one with the one side end of the high-frequency oscillator 11 the fifth dielectric stripline 37 connected non-reflective terminator 38b ; a sixth dielectric stripline 39 one end of which is the receiving antenna 20 connected is; and the mixer 16 which is any of the mixers completed by the described embodiments. The mixer 16 is between the other end of the fifth dielectric stripline 37 and the other end of the sixth dielectric stripline 39 for mixing a high-frequency signal coming from the fifth dielectric stripline 37 is input with one of the sixth dielectric strip line 39 entered high-frequency signal, after passing through the receiving antenna 20 is received to generate an intermediate frequency signal. It should be noted that the first and fifth dielectric stripline 32 and 37 at their mutually adjacent or coupled areas the branching device 12 form. The insulator 18 includes a circulator 14 , the fourth dielectric stripline 36 and the non-reflective terminator 38a , It should be noted that the first connection 34a and the second connection 34b in 10 the first connection 18a or the second connection 18b in 9 correspond.

The thus constructed high-frequency transmitting / receiving device 120 is similar in operation to the conventional high frequency transceiver. However, in the high-frequency transmitting / receiving apparatus due to the mixer 16 the mixing characteristics and the transfer characteristics of the mixer according to the characteristic of the high-frequency detecting element serving Schottky diode 45 , such as properties of noise caused by a resistive component of the Schottky diode 45 is generated, and the manner of mounting the Schottky diode 45 be matched accordingly. Thereby, a high-power high-frequency transmission / reception apparatus can be realized which offers excellent receiving sensitivity with stability.

Further, in the above embodiment, an output end of the mixer 16 preferably with a switch 17 which performs opening / closing (switching) in accordance with an external opening / closing control signal. When the switch 17 for performing the opening / closing (switching) in accordance with the control signal for opening / closing from the outside at the output end of the mixer 16 is provided, ie the output area 16c for outputting the generated intermediate frequency signal, even if, for example, insufficient isolation between the transmitting antenna 19 and the receiving antenna 20 causes a portion of the radio frequency signal intended to be transmitted to the receiving antenna 20 licks, then the switch can 17 be operated so that such intermediate frequency signal is turned off to not output the intermediate frequency signal to the leaked high frequency signal, and therefore, the high frequency signal to be received can be generated so that it is easy to identify.

Next, the high-frequency transmitting / receiving apparatus 130 according to the third embodiment with reference to 11 described. The high-frequency transmitting / receiving apparatus consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected RF selector switch 71 to select between a mode of outputting the high-frequency signal to an output end 71b as a high-frequency signal RFt intended for transmission and a mode of outputting the high-frequency signal to its other output end 71c to allow L0 as the local signal; a second RF selector 72 provided as a signal separating device having an input end 72b , an issue ending 72c and an input-output end 72a has, of which the input end 72b with the one output end 71b of the RF selector switch 71 to select between a mode of connecting the input / output end 72a with the input end 72b and a mode of connecting the input / output end 72a with the issue end 72c to allow; one with the input-output end 72a of the second RF selector switch 72 connected transmitting / receiving antenna 15 ; and a mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 is between the other issue end 71c of the RF selector switch 71 and the issue end 72c of the second RF selector switch 72 connected to the other output end 71c output local signal L0 with one through the transmitting / receiving antenna 15 received high-frequency signal to generate an intermediate frequency signal to mix.

In other words, the RF selector 71 has an input area 171a and two output areas 171b . 171c on, of which the input area 171a with the high-frequency oscillator 11 connected is. The RF selector switch 71 gives that through the high-frequency oscillator 11 given high-frequency signal selectively to the one output area 171b or the other output area 171c out. The second RF selector 72 provided as the signal separating device has the first terminal 72b , the second connection 72a and the third connection 72c on. By switching a connection mode between the first port 72b , the second port 72a and the third port 72c becomes the intended high-frequency signal for transmission from the RF selector switch 71 to the first connection 72b given, so that from the first connection 72b input high-frequency signal from the second port 72a is output and that from the second port 72a input high-frequency signal from the third port 72c is issued. The mixer 16 is with the other output area 171c of the RF selector switch 71 and the third port 72c of the second RF selector switch 72 connected.

Furthermore, in the above embodiment, an output end of the mixer 16 preferably with a switch 17 which performs opening / closing (switching) in accordance with an external opening / closing control signal.

When the intended high-frequency signal for transmission from the transmitting / receiving antenna 15 is output, a control signal from the outside to the selector switch 71 and the second selector 72 given that to the input area 171a given high-frequency signal from an output range 171b in the selector switch 71 is output and that to the first connection 72b given high-frequency signal to the second port 72a in the second selector 72 is given. If furthermore the high frequency signal through the transmitting / receiving antenna 15 is received, the control signal from the outside to the selector switch 71 and the second selector 72 given that to the input area 171a given high frequency signal from the other input area 171c in the selector switch 71 is output and that to the first connection 72b given high-frequency signal to the third port 72c is given in the second selector switch.

Furthermore, the high-frequency transmitting / receiving device 140 according to the fourth embodiment with reference to 12 described. The high-frequency transmitting / receiving apparatus consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected RF selector switch 71 to select between a mode of outputting the high-frequency signal to an output end 71b as a high-frequency signal RFt intended for transmission and a mode of outputting the high-frequency signal to its other output end 71c to allow L0 as the local signal; one with the one output end 71b of the RF selector switch 71 ie the other output area 171b , connected transmitting antenna 19 ; one relative to the other output end 71c of the RF selector switch 71 connected receiving antenna 20 ; and a mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 is between the other issue end 71c of the RF selector switch 71 and the receiving antenna 20 connected, in other words, its an input end 16a is with the other output area 171c connected and his other input end 16b is with the receiving antenna 20 connected to the other output end 71c output local signal L0 with one through the receiving antenna 20 received high-frequency signal to generate an intermediate frequency signal to mix.

Furthermore, in the above embodiment, an output end of the mixer 16 preferably with a switch 17 which performs opening / closing (switching) in accordance with an external opening / closing control signal.

When the intended high-frequency signal for transmission from the transmitting / receiving antenna 15 is output, a control signal from the outside to the selector switch 71 given that to the input area 171a given high-frequency signal from an output range 171b in the selector switch 71 is issued. If furthermore the high frequency signal through the transmitting / receiving antenna 15 is received, the control signal from the outside to the selector switch 71 given that to the input area 171a given high frequency signal from the other input area 171c in the selector switch 71 is issued.

Next, the high-frequency transmitting / receiving apparatus 150 described according to the fifth embodiment. As in the in 13 As shown in the block diagram shown, the high-frequency transmitting / receiving device consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected waveguide branch hybrid coupler 73 for branching the high frequency signal so that the branched high frequency signal components are at its output end 73b or his other issue end 73c can be issued; one between the one output end 73b and the other issue end 73c connected terminator 74 ; a second waveguide branch hybrid coupler 75 with a first connection 75b , a second connection 75a and a third port 75c of which the first connection 75b an issue from the one issue end 73b waveguide branch hybrid coupler 73 receives, wherein a high-frequency signal input from one of the terminals is again output from the other adjacent terminal, in order from the first to the third terminal; one between the first port 75b and the third port 75c connected terminator 76 ; one with the second port 75a of the second waveguide branch hybrid coupler 75 connected transmitting / receiving antenna 15 ; and a mixer 16 which is any of the mixers completed by the embodiments. The mixer 16 includes two input ends 16a and 16b , each between the other issue end 12c waveguide branch hybrid coupler 73 and the third port 75c of the second waveguide branch hybrid coupler 75 connected to the other end of the output 73c branched high frequency signal component with one through the transmitting / receiving antenna 15 received high-frequency signal to generate an intermediate frequency signal to mix.

Next, the high-frequency transmitting / receiving apparatus 160 described according to the sixth embodiment. As in the in 14 As shown in the block diagram shown, the high-frequency transmitting / receiving device consists of: a high-frequency oscillator 11 for generating a high-frequency signal; one with the high frequency oscillator 11 connected waveguide branch hybrid coupler 73 for branching the high frequency signal so that the branched high frequency signal components are at its output end 73b or his other issue end 73c can be issued; one between the one output end 73b and the other issue end 73c connected terminator 74 ; one with the other output end 73b waveguide branch hybrid coupler 73 connected transmitting antenna 19 ; one with the other output end 73c waveguide branch hybrid coupler 73 relatively connected receiving antenna 20 and a mixer 16 which is any of the mixers completed by the aforementioned embodiments. The mixer 16 includes two input ends 16a and 16b , each between the other issue end 12c waveguide branch hybrid coupler 73 and the receiving antenna 20 connected to the other end of the output 73c branched high frequency signal component with a through the receiving antenna 20 received high-frequency signal to generate an intermediate frequency signal to mix.

In each of the radio frequency transceivers 130 . 140 . 150 . 160 For example, the radio frequency transmission line should preferably be used under a nonradiative dielectric line, a dielectric waveguide line, a waveguide, a dielectric waveguide, a stripline, a Microstrip line, a coplanar line and a slot line can be selected.

Furthermore, both the RF selector switch 71 as well as the second RF selector switch 72 analogous to the design of the modulator 13 be designed.

Preferably, the RF selector switch 71 a branching device for branching an input high frequency signal so that the branched high frequency signal components are output to one of its output end and to another output end, respectively, and having first and second PIN diodes connected to the one and the other output ends of the branching device, respectively , At least one of the first and second PIN diodes is connected to a bias circuit for applying a forward bias voltage. In this case, at least one of the first and second PIN diodes exhibits a low impedance, and therefore, even if the first and second PIN diodes are switched, the impedance can be made constant low and stabilized when viewed from the input side of the high-frequency signal (the Side of the high-frequency oscillator 11 ) is seen. This enables a load change in the high-frequency oscillator 11 to suppress without using an isolator or the like device, and thereby to stabilize the oscillation frequency of the high-frequency signal.

In each of the radio frequency transceivers 110 . 120 . 130 . 140 For example, due to the mixer, the mixing characteristics and the transmission characteristics of the mixer can be suitably adjusted according to the characteristic of the high-frequency detection element and the manner of mounting the high-frequency detection element. Thereby, a high-power high-frequency transmission / reception apparatus can be realized which offers excellent receiving sensitivity with stability.

In the high-frequency transmitting / receiving apparatus, each of the first to sixth dielectric strip lines should 22 . 23 . 25 to 27 . 32 . 33 . 35 to 37 and 39 preferably made of a resin material, for example, tetrafluoroethylene or polystyrene, and a ceramic material, for example, low-permittivity cordierite (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ) ceramics, alumina (Al ₂ O ₃ ) ceramics, and glass-ceramics. These materials show low loss on high frequency signals in a millimeter wave band.

Although the first to sixth dielectric strip lines 22 . 23 . 25 to 27 . 32 . 33 . 35 to 37 and 39 In each case, a substantially rectangular cross-sectional profile is obtained in a virtual plane which is perpendicular to a direction of extent, the corners can also be rounded in their case. That is, the dielectric strip line may have a cross-sectional profile of different shapes as long as the high-frequency signals are correctly transmitted.

As a material for the ferrite plates 24 . 34 For example, it is preferable to use a zinc-nickel-iron composite oxide (Zn _a Ni _b Fe _c O _x ) which is desirable especially for millimeter-wave signals.

Although the ferrite plate 24 . 34 is normally disc-shaped, it may have the shape of a regular polygon when it is seen in a plane, that is, from the side of a thickness direction. In this case, assuming that the number of the dielectric strip lines connected thereto is n (n is an integer of 3 or more), the planar configuration of the ferrite plate should preferably be a regular polygon with m sides (m is a whole Number of 3 or more, where m> n).

As material for the parallel plate conductors 21 . 31 and the associated pair not shown, a circuit board made of Cu, Al, Fe, Ag, Au, Pt, SUS (stainless steel), brass (Cu-Zn alloy) or the like is preferably used from the viewpoint of high electrical conductivity and excellent processability the same material is made. Also, an insulating plate made of ceramics or resin may be used, having formed on its surface layers of such conductor materials as mentioned above.

The non-reflective terminators 28 . 38a and 38b are each with the fifth dielectric stripline 27 , the fourth dielectric stripline 36 and the fifth dielectric stripline 37 connected. Such a non-reflective terminator is made by providing a film-like resistive element or a wave absorber at the upper and lower ends of each side surface (the surface which is in face-to-face relationship with neither the inner surface of the parallel plate conductor 21 . 31 still the inner surface of the associated pair not shown) is placed at the end of its respective dielectric stripline. At this time, a nickel-chromium alloy or carbon is suitable for use as a resistive element, while Permalloy or Sendust is suitable for use as a wave absorber. By using such a material, millimeter wave signals can be attenuated with high efficiency. It should be noted that the resistive element or the wave absorber may be formed of any other material as long as it enables the attenuation of millimeter-wave signals.

The substrate 40 . 44 is prepared by laminating on a main surface of a plate-shaped base substrate of tetrafluoroethylene, polystyrene, glass-ceramic, glass epoxy resin, epoxy resin and thermoplastic resin, for example, a so-called liquid crystal polymer, the reactor bias supply line 41 . 46 formed of a strip conductor or the like made of aluminum (Al), gold (Au), copper (Cu) and the like material.

It should be noted that a distinctive feature of the radio frequency transceiver 110 . 120 . 130 . 140 it is that it includes the mixer. In the present construction, the high-frequency transmission line for providing a connection among the circuit elements is not limited to the nonradiative dielectric line, but may be of another configuration such as a waveguide, a dielectric waveguide, a stripline, a microstrip line, a coplanar line, a slot line, a coaxial line, or a modified form of a high-frequency transmission line of such kind. The shape selection is made in consideration of the frequency band for use and purposes. Furthermore, the usable frequency band corresponding to the high-frequency signals is not limited to a millimeter-wave band, but may be a microwave band or even lower.

Instead of the circulator 14 For example, an antenna switch, a switch, a hybrid circuit, or the like may be used. Further, for constituting the high-frequency oscillator, the modulator and the mixer, a bipolar transistor, a field-effect transistor (FET) or an integrated circuit employing such elements (CMOS, MMIC, etc.) in place of a diode can be employed.

Next, a description will be given below of a radar apparatus, a vehicle equipped with the radar apparatus, and a small boat equipped with the radar apparatus.

The radar apparatus according to an embodiment comprises one of said high frequency transmitting / receiving apparatuses and a distance information detector for acquiring data on the distance to an object to be detected by processing the intermediate frequency signal output from the high frequency transmitting / receiving apparatus.

According to the radar apparatus, the high frequency transceiver enjoys better performance, i. H. It offers excellent receiving sensitivity with stability and allows transmission of high frequency signals with a high transmission power ON / OFF ratio. Thus, not only an object to be detected can be detected quickly and without exception, it is also possible to capture without exception both close and distant target objects.

The vehicle carrying a radar is equipped with the radar device just described above. The radar device is used to detect an object to be detected.

By virtue of its structure, the vehicle accompanying a radar, like a conventional vehicle carrying a radar, is capable of controlling its behavior on the basis of distance information detected by the radar device and of a driver in front of, for example, the presence of an obstacle on the road or the approach of another Warning vehicle by sound, light or vibration. In addition, in the radar-carrying vehicle, the radar apparatus reacts to detect an object to be detected quickly and invariably, such as an obstacle on the road or other vehicles. This makes it possible to adequately control the vehicle and appropriately alert the driver without causing abrupt reactions in the vehicle.

Further, even if the vehicle vibrates, this does not result in the above-described resistance of the trimmable chip resistor 3 varies, and even if the radar device is mounted outside the vehicle, the resistance is still difficult to vary with a change in temperature and humidity, and therefore the predetermined mixing characteristics and transmission characteristics can be advantageously maintained, so that the stable radar apparatus can realize a stable detection process ,

In particular, the vehicle carrying a radar has a wider field of application, including as a bicycle, as a bicycle with an auxiliary engine, as a vehicle in an amusement park and as a car on a golf course, and also as a steam train, electric train, automobile and motor vehicle for freight transport.

The radar-carrying small boat is equipped with the above-described radar apparatus. The radar device is for detecting an object to be detected.

Due to its structure, the small boat carrying a radar is like a conventional one A radar-borne vehicle is capable of controlling its behavior on the basis of the distance information detected by the radar device and warning an operator, for example, of the presence of an obstacle, for example a reef, or the approach of other vessels or vehicles by sound, light or vibration. Moreover, in the radar-carrying small boat, the radar apparatus reacts to quickly and without exception detect an object to be detected, for example, an obstacle such as a reef, or other ships or vehicles. This makes it possible to control the small boat correctly and to give an operator an appropriate warning without causing abrupt reactions in the small boat.

Further, even if the boat vibrates, this does not result in the above-described resistance of the trimmable chip resistor 3 varies, and even if the radar device is mounted outside the vehicle, the resistance is difficult to vary with a change in temperature or humidity, and therefore the predetermined mixing characteristics, transmission characteristics and the like can be maintained advantageous, so that the stable radar device for a stable operation Capture can realize.

The radar-carrying small boat can be used on boats of various types, which can be operated by operators with and without license or license, in particular a tractor whose total tonnage is less than 20 tons; a dinghy; a jet ski; a small perch fishing boat with outboard motor; an inflatable boat (rubber boat) with outboard motor; a fishing vessel; a sport fishing boat; a workboat; an old-fashioned houseboat; a trailer boat; a pleasure boat; a fishing boat; a yacht; a ocean-going yacht; a cruiser and a cruise ship whose total tonnage is 20 tons or more.

As described so far, there are provided: a mixer in which a bias supply circuit of a high-frequency detection element for constituting the mixer is provided with a preset variable resistor to satisfactorily tune mixing characteristics and transmission characteristics of the mixer; a high-frequency transmitting / receiving apparatus with the mixer, which is remarkable for its simple construction and performance and capable of providing an excellent receiving line having a high transmission power ON / OFF ratio by preventing a part a radio frequency signal intended for transmission is transmitted as an unwanted signal when a modulator is held in an OFF state; a radar apparatus having the high-frequency transceiver with excellent performance; a vehicle equipped with the radar device and a small boat equipped with the radar device.

[Example]

As an actual application example, the high-frequency transmitting / receiving device 110 as they are in the 6 and 7 shown constructed as follows. As two parallel plate conductors 21 (one of which is not illustrated in the figures), two pieces of 6 mm thick Al (aluminum) plates were placed at a pitch of 1.8 mm so that their surfaces faced each other in the thickness direction. Between the Al plates were the first to fifth dielectric lines 22 . 23 and 25 to 27 made of cordierite ceramic with a relative dielectric constant of 4.8. Each of the dielectric strip lines has a sectional profile of 1.8 mm in height and 0.8 mm in width in a virtual plane perpendicular to an extending direction of the wires. As a circulator 14 were two pieces of ferrite plates 24 , each having a diameter of 2 mm and a thickness of 0.23, prepared. One of them became in close contact with a parallel plate conductor 21 (the upper parallel plate conductor) while the other is in close contact with the other parallel plate conductor 21 (the lower parallel plate conductor) was brought. These ferrite plates were arranged concentrically facing each other. Radial around the circumference of the ferrite plate 24 are the second dielectric stripline 23 , the third dielectric stripline 25 and the fourth dielectric stripline 26 arranged. Furthermore, the branching device became 12 formed by a central region of the first dielectric strip line 22 and a center region of the fifth dielectric strip line 27 were placed close to each other, with a clearance of 2.1 mm between their closest adjacent areas. The non-reflective terminator 28 is with a side end of the high-frequency oscillator 11 the fifth dielectric stripline 27 connected. Furthermore, the modulator 13 formed by between the first dielectric strip line 22 and the second dielectric stripline 23 a millimeter-wave modulation switch has been placed from the substrate 40 which was made of 0.2 mm-thick low-dielectric-constant thermoplastic resin-made organic resin substrate (relative dielectric constant εr = 3.0). On a main surface of the high-frequency wave modulation switch (with its surface opposite to the surface of the first dielectric strip line 22 was turned) the throttle bias supply 41 made of copper with wide stripline and narrow stripline in 8th are shown, formed and arranged in an alternative manner. The length of the wide strip line is given by the expression: where λ _1/4 = 0.7 mm (λ ₁ is equal to 2.8 mm with respect to the wavelength of about 4 mm of a high-frequency signal at a frequency of 76.3 GHz, that is, it is shortened in wavelength on the dielectric substrate), and the length of the narrow strip line is given by the expression: where λ _1/4 = 0.7 mm. The widths of the wide stripline and the narrow stripline were set to 1.5 mm and 0.2 mm, respectively. Next was called high-frequency oscillator 11 a pill-type voltage controlled oscillator (VCO) using a Gunn diode. The VCO has been connected to the other end of a waveguide, one end of which is inserted into a through hole in a part of the parallel plate conductor 21 is drilled in which the electric field of a standing wave, the one through the first dielectric stripline 22 propagating high frequency signal is strong. Then the transmitting / receiving antenna became 15 with one end of the third dielectric stripline 25 opposite to the ferrite plate 24 connected to the other end connected. It should be noted that the ferrite plate 24 is made of a material showing a relative dielectric constant of 13.5 and a saturation magnetization of 3,300 G (Gauss) (the magnetic flux density Bm measured according to Japanese Industrial Standard JIS C2561 by a specific DC magnetometry technique).

Last time was called mixer 16 a balancing mixer made as follows. As in 2 has been shown have become a center portion of the fourth dielectric strip line 26 and a center region of the fifth dielectric strip line 27 placed in close proximity to each other, with a distance of 1.1 mm between their nearest adjacent areas. Then, a high frequency detection area was respectively formed at one end of the fourth dielectric strip line 26 opposite to the ferrite plate 24 connected other end and one end of the fifth dielectric strip line 27 opposite to the branching device 12 arranged connected to the other end. The high frequency detection area consists of the substrate 44 which was made of a 0.2 mm-thick low-dielectric-constant thermoplastic resin-made organic resin substrate (relative dielectric constant εr = 3.0). As in 3 was shown on a main surface of the high-frequency detection region (with its surface opposite to the surface of the fourth and fifth dielectric strip line 26 . 27 facing) the choke bias supply line 46 made of copper with wide strip cables 46a and narrow strip lines 46b , which are arranged in an alternative manner, formed. The length of the wide stripline 46a is given by the expression: where λ _1/4 = 0.7 mm (λ ₁ is equal to 2.8 mm with respect to the wavelength of about 4 mm of a high-frequency signal at a frequency of 76.3 GHz, that is, it is in the wavelength on the shortened dielectric substrate), and the length of the narrow stripline 46b is given by the expression: where λ _1/4 = 0.7 mm. The widths of the wide stripline 46a and the narrow stripline 46b were set at 1.5 mm and 0.2 mm, respectively. As in the in 1 shown circuit diagram were further the DC voltage source 5 and the trimmable chip resistor 3 with the end of the choke bias supply line 46 connected, as in 5A is shown. It should be noted that the line lengths of the first and second dielectric strip lines 22 and 23 were determined in such a manner that the phase difference δ between the high-frequency signals Wa ₂ and Wb ₂ is substantially equal to π at 76.3 GHz: the center frequency of a high-frequency signal intended for transmission.

In the radio frequency transceiver thus constructed, the resistance of the trimmable chip resistor was initially established 3 set correctly. Then one was through the Schottky diode 45 ( 2 ) of the mixer 16 passing bias current to vary within a range of 0 to 5 mA. In this state, the intensity Pa ₂ and Pb _{2 of} the high frequency signals Wa ₂ and Wb _{2 were} measured by means of a vector network analyzer designed for use in a millimeter wave band, as follows. First, the VCO was disconnected from the end of the waveguide so that a first test port (test port 1) of the vector network analyzer could be connected to the end. After that, the transmitting / receiving antenna became 19 from the end of the third dielectric stripline 25 disconnected so that a second test port (test port 2) could be connected to the end. Then, the transmission characteristics S ₂₁ between the first and second test ports were measured. When taking a measurement on the through the modulator 13 which was placed in an OFF state, transmitted high-frequency signal Wa ₂ has been at this time an electromagnetic, wave blocking Metal plate between the first dielectric strip line 22 and the fifth dielectric stripline 27 inserted to interrupt the high-frequency signal Wb ₂ . If, on the other hand, a measurement is made at the end of the output 13b of the modulator 13 in that instead of the high frequency modulator switch, reflected high frequency signal Wb _{2 was} measured, an electromagnetic wave blocking metal plate was interposed between the first dielectric strip line 22 and the second dielectric stripline 23 inserted to interrupt the high-frequency signal Wa ₂ . That is, the measurement of the transmission characteristics S ₂₁ was performed for each of the high-frequency signals Wa ₂ and Wb ₂ on an individual basis. In the present case, under the condition that the intensity of a high-frequency signal output from the first test terminal is 0 dBm, the intensities Pa ₂ and Pb _{2 were derived} on the basis of the measured values of the transmission characteristics S ₂₁ . 15 is a diagram showing an example of the measurement results.

15 FIG. 15 is a diagram showing the intensities Pa ₂ and Pb _{2 of} the high-frequency signals Wa ₂ and Wb ₂ as in the example of application of the high-frequency transmitting / receiving apparatus 110 were observed. In 15 a bias current in the mixer is indicated along the horizontal axis (unit: mA) and the intensity of the high frequency signal is indicated along the vertical axis (unit: dBm). Furthermore, the intensity Pa _{2 of} the high frequency signal Wa _{2 is} plotted on a frequency of 76.3 GHz by filled circles, whereas the intensity Pb _{2 of} the high frequency signal Wb _{2 is} plotted on a frequency of 76.3 GHz by filled squares.

How out 15 As can be seen, the intensity Pb _{2 of} the high-frequency signal Wb ₂ varies depending on the value of the bias current present in the mixer. Thus, it was confirmed that by appropriately changing the resistance of the trimmable chip resistor 3 through the Schottky diode 45 ( 2 ) through current can be made to vary and thereby the impedance at the output ends 26b and 27b the fourth and fifth dielectric strip lines 26 and 27 be varied, which is why a change in the transmission coefficient between the two input ends 16a and 16b of the mixer 16 results. For example, as shown in the present example, by adjusting the resistance of the trimmable chip resistor 3 in such a manner that the bias current in the mixer is 2 mA, it is ensured that the intensity Pa _{2 of} the high-frequency signal Wa ₂ and the intensity Pb _{2 of} the high-frequency signal Wb ₂ are substantially equal.

Next, the high frequency transceiver became 110 operated under actual conditions to measure ON / OFF ratio characteristics at a bias current of 0 to 2.5 mA in the mixer. Initially, the VCO was operated to oscillate stably, with its oscillation energy held immutable. Subsequently, the transmitting / receiving antenna 15 from the end of the third dielectric stripline 25 so that a test port of a spectrum analyzer designed for use in a millimeter wave band could be connected to the end. In this state was used for each case in which the modulator 13 is placed in an ON state, and in the case where it is placed in an OFF state, the intensity of a high-frequency signal output from the end is measured while frequency-scanning has been performed step by step. This determined the relationship between two measurements, namely the ON / OFF ratio. The measurement results are in an in 16 shown diagram. In the diagram, the high-frequency signal intensity obtained as transmission power is when the modulator 13 is placed in an ON state, defined by W_on (unit: watts), while the high frequency signal intensity obtained as transmission energy when the modulator 13 is placed in an OFF state, defined by W_off (unit: watts). In the present case, the frequency of the high frequency signal has been caused to vary in a range between about 75.8 GHz and about 76.8 GHz.

16 Fig. 15 is a diagram showing the transmission power ON / OFF ratio characteristics as observed in the application example of the high-frequency transmission / reception apparatus. In 16 is a frequency along the horizontal axis (unit: GHz), and the transmission power ON / OFF ratio is indicated along the vertical axis (unit: dB) represented by a reciprocal number (-10log (W_on / W_off)) , Further, the representative actual measured values are the transmission power ON / OFF ratio characteristics corresponding to 0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 mA, respectively Mischers), each indicated by open squares, open circles, open triangles, solid squares, solid circles and solid triangles. It should be noted that in 16 the ON / OFF ratio is represented by a reciprocal number. Therefore, the smaller the drawn actual measured values, the better the ON / OFF ratio is, that is, the better the transmission power ON / OFF ratio characteristics are.

As from the in 16 When the bias current in the mixer is 2.0 mA at which the intensity Pa _{2 of} the high-frequency signal Wa ₂ and the intensity Pb _{2 of} the high-frequency signal _wb2 are substantially equal, the highest ON / OFF ratio becomes _apparent 76.3 GHz: the center frequency of a high-frequency signal intended for transmission. It has therefore been found desirable to tune to the resistance of the trimmable chip resistor 3 in such a manner that the relationship between the intensity Pa _{2 of} the high-frequency signal Wa ₂ and the intensity Pb _{2 of} the high-frequency signal Wb _{2 is given} by: Pa ₂ = Pb ₂ . This will result in the region between the issue end 13b of the modulator 13 and the circulator 14 the high-frequency signals Wa ₂ and Wb ₂ are synthesized in phase opposition and cancel each other, thereby efficiently causing attenuation. This makes it possible to achieve a high transmission power ON / OFF ratio by preventing a part of the radio frequency signal intended for transmission from being sent as an unwanted signal when the modulator 13 is kept in an OFF state.

When the mixing characteristics and transfer characteristics of the mixer are adjusted, the resistance of the trimmable chip resistor becomes 3 caused by the lowest resistance of the trimmable chip resistor 3 To get bigger step by step. By increasing the resistance of the trimmable chip resistor 3 can the through the Schottky diode 2 passing through current can be reduced. The resistance of the trimmable chip resistor 3 is increased until passing through the Schottky diode 2 current reaching about 2.0 mA, whereby the transmission power ON / OFF ratio can be greater. Because the trimmable chip resistor 3 is an irreversible resistance, the adjustment of the mixing characteristics and transfer characteristics of the mixer is thus accomplished by varying that through the Schottky diode 2 in one direction passing current, in this case by reducing, performed.

By an evaluation test similar to that performed in the hitherto described high frequency transmitting / receiving apparatus, it has been confirmed that it is the high frequency transmitting / receiving apparatus 120 also manages to provide a high transmission energy ON / OFF ratio.

Recently, a radar apparatus equipped with the high-frequency transmission / reception apparatus has been constructed. The radar apparatus was subjected to a radar detection test to evaluate its ability to detect an approaching target. From the test result, it was confirmed that the radar apparatus, in which tuning was performed in the above-mentioned manner for the mixer to respond appropriately, is capable of generating range information quickly and unconditionally.

As described above, the following is provided: a mixer in which a bias supply circuit of a high-frequency detection element for constructing the mixer is provided with a preset variable resistor to thereby satisfactorily tune characteristics such as mixing characteristics and transfer characteristics of the mixer; a high-frequency transmitting / receiving device with the mixer, which is remarkable for its simple construction and performance and is able to provide excellent reception performance with a high transmission power ON / OFF ratio by preventing a part of a for Sending an intended high frequency signal as an unwanted signal when a modulator is held in an OFF state; and a radar apparatus capable of performing radar detection quickly and unconditionally.

Claims (3)

Radio frequency transceiver comprising: a high frequency oscillator ( 11 ) for generating a high-frequency signal; • one with the high-frequency oscillator ( 11 ) connected branching device ( 12 ) with two output areas ( 12b . 12c ) for branching the high-frequency signal generated by the high-frequency oscillator ( 11 ), and outputting the branched high-frequency signal components from one or the other of the two output ranges ( 12b . 12c ) • one with the one output area ( 12b ) of the branching device ( 12 ) connected modulator ( 13 ) for modulating the branched high frequency signal component and outputting a high frequency signal intended for transmission; A signal separation device ( 14 ) with a first connection ( 14a ), a second port ( 14b ) and a third port ( 14c ) for receiving the radio frequency signal intended for transmission from the modulator ( 13 ) at the first connection ( 14a ) to output from the first port ( 14a ) for transmitting intended radio frequency signal from the second port ( 14b ) and for issuing one from the second port ( 14b ) input high-frequency signal from the third terminal ( 14c ); • one with the second connection ( 14b ) of the signal separation device ( 14 ) connected transmitting / receiving antenna ( 15 ); and a mixer ( 16 ), where from the two input ends ( 16a . 16b ) an input end ( 16a ) with the other output area ( 12c ) of the branching device ( 12 ), and the other input end ( 16b ) with the third connection ( 14c ) of the signal separation device ( 14 ), for mixing the from the other output area ( 12c ) of the branching device ( 12 ) output branched high-frequency signal component with a through the transmitting / receiving antenna ( 15 ) received radio frequency signal and for generating an intermediate frequency signal, • wherein the mixer ( 16 ) - a coupler with two input ends ( 16a . 16b ) and one or two output ends ( 16c ); - one at the end of dispensing ( 16c ) of the coupler high-frequency detection element ( 2 ); and - a bias supply circuit connected to the high-frequency detection element ( 3 - 5 ) for supplying an adjustable bias current to the high-frequency detection element; Wherein the bias supply circuit ( 3 - 5 ) a preset variable chip resistor ( 3 ) for controlling the bias current generated by the high-frequency detection element ( 2 ), wherein a transmission coefficient between the two input ends ( 16a . 16b ) of the mixer ( 16 ) with the chip resistor ( 3 ) is set to have the following expression: Pa ₂ = Pb ₂ , where Pa _{2 is} the intensity of the signal Wa2 generated by the modulator ( 13 ), which is placed in an OFF state, and Pb2 is the intensity of the high frequency signal Wb2 coming from the other output area (FIG. 12c ) of the branching device ( 12 ) over the mixer ( 16 ) and the signal separation device ( 14 ) to the output area of the modulator ( 13 ) and then from the output end of the output range of the modulator ( 13 ), wherein a line length between the one output end ( 12b ) of the output area of the branching direction ( 12 ) and the modulator ( 13 ) or a line length between the other output end ( 12c ) of the output area of the branching device ( 12 ) and the modulator ( 13 ), the mixer ( 16 ) and the signal separation device ( 14 ), it is determined that the following expression applies: δ = (2N + 1) · π (N stands for an integer), where δ stands for the phase difference between the high-frequency signals Wa ₂ and Wb ₂ at a center frequency , Radar device with: the high-frequency transmitting / receiving device according to claim 1, and a distance information detector for acquiring data on a distance to an object to be detected by processing the intermediate frequency signal output from the high frequency transmitter / receiver. A radar-borne vehicle having the radar apparatus according to claim 2, which is used to detect an object to be detected.

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